One could argue, of course, that masks on planes still pass muster. Isn’t the inconvenience small, compared with the catastrophic risks faced by people who can’t get vaccinated, or whose immune systems are too compromised to mount a strong response to the vaccine?

Fair enough, but then one also has to ask about the other side of that cost-benefit equation: Exactly how many coronavirus cases are being prevented by requiring people to wear masks on planes? Airplanes are extremely well ventilated, which is why there have been so few outbreaks traced to air travel compared with other indoor environments. And while masks do offer some added protection against whatever risk remains, the cloth and surgical masks being worn by most people aren’t really all that effective — even before you consider how often they are pulled down to eat, or drink, or just gulp a little air.

Those masks also have costs for the people forced to wear them, as I recently found out when a series of badly timed connecting flights sent me sprinting through airports in my mask. (Or attempting to sprint; I missed my planes.) And while this is a minor consideration, some of the side effects of mask mandates are not; a relative with chronic obstructive pulmonary disease cannot fly because it is too hard for them to breathe in a mask.